This invention relates generally to combustion devices, and more specifically to torches.
The relay of the Olympic torch is a tradition of the modern day Olympics. The first Olympic torch relay traveled from Olympia, Greece to Berlin, Germany as part of the 1936 Opening Ceremony. The torch passed through seven countries and the relay was completed solely by runners. A torch relay has been held, in one form or another, at every Olympics since.
For modern day Olympic torch relays, several thousand participants may act as torch-bearers along the torch relay. For example, in the 2002 Salt Lake City Olympics, over 11,000 torch-bearers carried some form of torch over a 13,500-mile circuitous trek that covered 46 states in the United States. The relay lasted 65 days, and in addition to running torch-bearers, torches were carried by automobile, airplane, train, ship, dogsled, skiers, horse-drawn sleigh, snowmobile, ice skaters, and various other forms of transportation.
For the 2002 Salt Lake City Games, each running torch-bearer ran or walked with a torch an average of two-tenths of a mile. Because the torch-bearers often like to keep their torches as a souvenir, each torch-bearer often uses his or her own torch. This may cause a problem, in that the torches need to look the same, and burn the same, over the entire torch relay. Ideally, during the entire trek of each torch-bearer, a respective torch-bearer""s torch needs to remain lit while emitting a bright yellow, consistently-sized flame. In addition, torches need to continue to remain lit through all types of weather, including rain and temperatures as low as negative 20 degrees Fahrenheit. Finally, the stable, consistent flame must be maintained as fuel in the torch is consumed.
The present invention provides a fuel delivery system and burner that is suitable for an Olympic torch. The fuel delivery system and burner may be used for other torches, for example, tiki torches.
In accordance with one aspect of the present invention, the fuel delivery system includes a regulator mounted in a torch body and in fluid communication with a fuel supply, such as a fuel canister or tank. The regulator maintains the fuel exiting the fuel canister at a substantially constant pressure within a regulator cavity.
Fuel passes from the regulator cavity into a tube, or conduit, that extends through the path of a flame that is produced by the burner. The tube preferably is shaped into a coil around the area of the flame so that the coil is heated by the flame. The heated coil assures that liquid fuel in the coil is vaporized as it passes through the coil. In addition, the coil may act as a flame spreader, giving the flame a much larger, fuller appearance. The tube and therefore the fuel flow continue through and beyond the coil and into the top of the torch body.
The heated coil and tube are preferably formed of a thermally conductive material, such as brass or copper. In addition, the torch body is also made of a thermally conductive material. In this manner, the heat on the coil may be transferred to the torch body, permitting the torch body to remain heated during operation of the burner. In this manner, the regulator may vaporize some or all of the fuel before it even enters the tube. In addition, the heat from the tube heats the torch body to overcome the cooling caused by vaporization of the fuel.
If some liquid passes into the tube, the routing of the fuel through the flame via the coil assures that all fuel is vaporized before it reenters the top of the torch body. When the fuel flows through the tube and into the top of the torch body, it enters a gas tip chamber. A gas tip is seated in the top portion of the chamber, and is configured to regulate a flow of the vaporized fuel into a burner tube.
In accordance with one aspect of the present invention, the burner tube includes an internal passage and an outer passage. Fuel vapor flows through each of these passages, and escapes the burner tube at a distal end. The outer flow of gas is slow, and does not aspirate air, causing the flame to remain attached to the burner and to burn yellow. The inner flow of gas adds velocity, helping the burner flame to be wind resistant. This inner flow of vapor fuel does not draw in air because it is surrounded by the vapor fuel flow from the outer flow. The resultant flame is soft yellow, stays attached to the burner, does not draw in air, and still has a good velocity away from the burner, and thus is wind resistant.
Other advantages will become apparent from the following detailed description when taken in conjunction with the drawings, in which: